Simplify the following expression: ${2(3a-3)-2(-2+a)}$
Distribute the ${2}$ into the first set of parentheses: $ {2(}\gray{3a-3}{)} - 2(-2+a) $ $ {6a-6} - 2(-2+a) $ Distribute the ${-2}$ into the parentheses: $ 6a-6 {-2(}\gray{-2+a}{)} $ $ 6a-6 + {4-2a} $ Rewrite the expression to group the ${a}$ terms and numeric terms: $ {6a - 2a} {-6 + 4}$ Combine the ${a}$ terms: $ {4a} {-6 + 4}$ Combine the numeric terms: $ {4a} {-2}$ The simplified expression is $4a-2$